Last week, a grand jury was convened in St. Louis County, Mo., to examine the evidence against the police officer who killed Michael Brown, an unarmed black teenager, and to determine if he should be indicted. Attorney General Eric Holder even showed up to announce a separate federal investigation, and to promise that justice would be done. But if the conclusion is that the officer, Darren Wilson, acted improperly, the ability to hold him or Ferguson, Mo., accountable will be severely restricted by none other than the U.S. Supreme Court.

In recent years, the court has made it very difficult, and often impossible, to hold police officers and the governments that employ them accountable for civil rights violations. This undermines the ability to deter illegal police behavior and leaves victims without compensation. When the police kill or injure innocent people, the victims rarely have recourse.

The most recent court ruling that favored the police was Plumhoff vs. Rickard, decided May 27, which found that even egregious police conduct is not “excessive force” in violation of the Constitution. Police officers in West Memphis, Ark., pulled over a driver because the car had only one operating headlight. Rather than comply with an officer’s request to get out of the car, the driver sped away. The police chased the car for more than five minutes, reaching speeds of over 100 mph. Eventually, officers fired 15 shots into the car, killing both the driver and a passenger.

The Supreme Court reversed the decision of the 6th U.S. Circuit Court of Appeals and ruled unanimously in favor of the police. Justice Samuel Alito said that the driver’s conduct posed a “grave public safety risk” and that the police were justified in shooting at the car to stop it. The court said it “stands to reason that, if police officers are justified in firing at a suspect in order to end a severe threat to public safety, the officers need not stop shooting until the threat has ended.”

This is deeply disturbing. The Supreme Court now has said that whenever there is a high-speed chase that could injure others — and that would seem to be true of virtually all high-speed chases — the police can shoot at the vehicle and keep shooting until the chase ends. Obvious alternatives could include shooting out the car’s tires, or even taking the license plate number and tracking the driver down later.

The court has also weakened accountability by ruling that a local government can be held liable only if it is proved that the city’s or county’s own policy violated the Constitution. In almost every other area of law, an employer can be held liable if its employees, in the scope of their duties, injure others, even negligently. This encourages employers to control the conduct of their employees and ensures that those injured will be compensated.

Because it is so difficult to sue government entities, most victims’ only recourse is to sue the officers involved. Here, too, the Supreme Court has created often insurmountable obstacles. The court has held that all government officials sued for monetary damages can raise immunity as a defense. Police officers and other law enforcement personnel who commit perjury have absolute immunity and cannot be sued for money, even when it results in the imprisonment of an innocent person. A prosecutor who commits misconduct also has absolute immunity to lawsuits.

When there is not absolute immunity, police officers are still protected by qualified immunity when sued for monetary damages. The Supreme Court, in an opinion by Justice Antonin Scalia in 2011, ruled that a government officer can be held liable only if “every reasonable official” would have known that his conduct was unlawful.

The Supreme Court has used this doctrine in recent years to deny damages to an eighth-grade girl who was strip-searched by school officials on suspicion that she had prescription-strength ibuprofen. It has also used it to deny damages to a man who, under a material-witness warrant, was held in a maximum security prison for 16 days and on supervised release for 14 months, even though the government had no intention of using him as a material witness or even probable cause to arrest him. In each instance, the court stressed that the government officer could not be held liable, even though the Constitution had clearly been violated.

Taken together, these rulings have a powerful effect. They mean that the city of Ferguson and the officer who shot Michael Brown will most likely never be held accountable in court. How many more deaths and how many more riots will it take before the Supreme Court changes course?

Erwin Chemerinsky, dean of the School of Law at the University of California, Irvine, is the author of the forthcoming “The Case Against the Supreme Court.” His email address is echemerinsky@law.uci.edu.

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